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<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <style>
        *{
            color: #0f0;
            border: #ff0;
            /* width: 30px; */
        }
    </style>
</head>
<body>
    <ul>
        <li >列表一</li>
        <li id="a">列表二 </li>
        <li>列表三</li>
    </ul>
    <ol>
        <li>有序列表一</li>
        <li>有序列表二</li>
        <li>有序列表三</li>
</body>
</html>